Dear Car Talk:
Is it good to keep the traction control switch off in summer driving? -- Sean
Why would you do that, Sean?
Traction control is kind of the flip side of anti-lock brakes. The anti-lock braking system (ABS) measures the speed of each wheel.If you're stopping the car, and one of the wheels suddenly goes slower than the others, the ABS concludes that it's locked up -- which can cause you to lose control of the car. So, it pulses the brake many times a second to give you maximum stopping power just short of locking up the wheel.
Traction control uses that same system to detect if one wheel is spinning faster than the others. If it is, the system concludes that the wheel has lost traction and is spinning, which can also lead to loss of control of the vehicle. So, it uses the ABS to slow down that wheel until it regains traction.
Neither of these systems work unless and until you need them. They're always on standby. And that's the way you want them.
While snow or ice would be the most obvious reasons for a wheel to spin, they're not the only ones. A summer rain, some leaked oil, or a patch of loose dirt or sand can cause a wheel to lose traction. And when that happens, you want your traction control to work.
Plus, there's absolutely no downside to leaving it on. You're not "wasting" anything or wearing anything out. It's inactive until it gets a signal that a wheel is spinning. Turning it off in the summer would be like turning off your home's fire alarm when it's raining. Sure, you could. But why would you?